La gestión de la variabilidad: un reto pendiente para los servicios de urgencias hospitalarios

Abstract

The aim of this study is to verify the existence of stable patterns of urgent demand and analyze the demand variability in the emergency department of a public hospital according to the arrival pattern, severity of patients' condition and the clinical area to adjust its resources. For this purpose, we performed a retrospective descriptive observational study of emergencies attended from 2008 to 2010 in the "Juan Ramón Jiménez" General Hospital (Huelva, Spain), with a sample of 343,233 visits. The time between consecutive arrivals of patients and the arrival patterns according to severity and clinical area were calculated using Microsoft Excel and Stat::Fit. Quarterly differences were determined using the Kruskal-Wallis test. As the results, we note that the mean value of the interarrival time, independently of the quarter (p<.05), was 2 - 4 minutes from 10:00 a.m. to 10 p.m. and 15-20 minutes from midnight to 8:00 a.m. The Priority (P) I Patients arrived every 119.05±136.71 minutes, the PII patients every 75.96±97.58 minutes, the PIII patients every 22.62±33.47 minutes and the PIV patients every 6.37±10.53 minutes. PI and PII had a consistent arrival pattern, PIV had a fluctuating pattern, and PIII had an intermediate level, with no quarterly differences (p<.05). The arrival rate peaks at 1:00 p.m. on Monday in the Medical-Surgical area, at 10:00 p.m. on Monday for the Trauma area, and at 1:00 p.m. on Sunday for the Pediatric area. In conclusion the study shows that interarrival times and average arrival rates of patients have a defined and reproducible pattern for each level of severity and clinical area, which forces us to rethink the fixed capacity model and oriented towards flexibility of resources.